Casing head valve



Oct. 10, 1933. J. H. HOWARD CASING HEAD VALVE Filed March 24, 1931 2 Sheets-Sheet 1 Oct. 10, 1933.

J. H. HOWARD CASING HEAD VALVE 2 Sheets-Sheet 2 Filed March 24, 1951 gn ve'nto'c James H. Hawa/ral.

Patented Oct. 10, 1933 UNITED STATES PATENT" OFFICE CASING HEAD VALVE ration of Texas Applioation March 24, 1931. Serial No. 524,791

This invention relates generally to deep well apparatus and specifically to casing head valves.-

on the casing above the valve. The valve is used 1 to close the casing when the drill stem is withdrawn for repairs or other purposes. The valve cannot be closed when the drill stem is in the casing. If during drilling operations, the drill encounters fluid under high. pressure, what is known as a blow out often occurs; that is, fluid rushes upwardly between the casing and the drill stem; and the drill stem may be blown out of the casing. This is now prevented by a device called a blow out preventer which engages the drill stem and is received and retained by the casing head. 1'

This invention has for its principal general object the provision of a new and improved casing head valve adapted to serve both as a master gate valve, and as a casing head.

A specific object of the invention is to provide a casing head valve and associated parts 'so constructed that a drill stem may be divided at a point adjacent thereto, after which the valve may be closed to prevent a blow out.

Other objects will hereinafter appear.

Two preferred embodiments of the invention are illustrated by the accompanying drawings, of which Fig. 1 is a fragmentary, partly sectional side elevation of one embodiment of the valve combined with conventional elements; Fig. 2,

a detail view of the dog actuating device; Fig. 3, aslgorizontal section on the line 3--3 of Fig. 1; Fig. a view similar to Fig. 1 of another embodiment; and Fig. 5, a horizontal section on the line 55 of Fig. 4.

Referring to Figs. 1, 2 and 3, the valve body is indicated at 1. It is connected at its lower end by threads 2 to the upper end of easing 3.

In the lower portion of the valve body are v branch passageways 4 through which muddy water, or slush, pumped through the drill stem 5 and rising upwardly in the annular space between the drill stem 5 and the casing 3, may be conveyed back to the pumps, not shown. When a blow out occurs, muddy water may be pumped through these branch passageways downwardly in the space between the casing and the drill stem.

The valve or gate 6 is movable bythe hand wheel '7 transversely across the main fluid passageway in the valve body to engage the valve seat 8. Such transverse movement of the valve 6 by the hand wheel '7 is eflected by the rotatable but longitudinally immovable stem 9 which is threaded in the valve as indicated at 10 in Fig. 4.

The opening 11 in the upper end of the valve body is much larger than is the opening 12 in the lowerend of the valve body. Intermediate these openings is a downwardly tapered seat 13. The internal diameter of the upper extremity of this seat is substantially equal to the diameter of the upper opening 11; and the internal diameter of the lower portion of this seat is substantially equal to the diameter of theopening 12.

The opening 11 is made large to permit the blow out preventer 14 to be moved into the fluid passageway of the body and upon the seat 13 below the valve 6. This blow out preventer is described and. claimed in my pending application for Letters Patent of the United States, Serial No. 432,050, filed February '28, 1930. As shown in Figs. 1, 2 and 3, it is substantially frusto-conical and comprises a pair of sections 15 and 16, hinged as indicated at 17 so that they may be placed around the drill stem 5. The sections are held together by the latch 18. Between the upper and lower metallic rings 19 and 20 is a rubber ring 21. The upper ring 19 is adapted to be held in place by dogs 22, yieldably held in their active positions by springs 23; and movable into their inactive positions by any suitable device such as the tool 24 (Fig. 2) comprising a cylindrical head adapted to be rotated in openings 19a in ring 19 and having an eccentric socket 24a for the reception of thepins 22a carried by the dogs. The dogs are guided in their inward and outward movements by suitable pins 19b stationary in the ring 19 and fitting within the slots 22b in the dogs.

The upper portion of the seat 13 of the valve body is provided with serrations for the reception of the teeth of the dogs 22.

The blow out preventer fits the drill stem 5 snugly, and is, therefore, engaged by the coupling 25.

26 indicates a guide for the drill stem which serves to protect the threads 2'7 by which the valve body may be connected to a production flow pipe after the well has been drilled.

If, during drilling operations, fluid underhigh pressure is encountered, the blow out preventer may be clamped about the drill stem above the valve body and permitted to fall through the opening 11 upon the seat 13. The drill stem is then lowered. The coupling 25 will engage the upper ring 19; the weight of the drill stem will force the upper ring 19 downwardly; and, as the ring 20 is held stationary by the seat, the

rubber packing ring 21 will be radially expanded into sealing engagement with the seat 13. The dogs 22 are thereupon automatically moved by the springs 23 into locking engagement with the seat.

The space between the casing and drill stem is thereby sealed, and should the pressure thereafter become sufficiently great to elevate the drill stem 5, that coupling thereon immediately below the coupling 25 will be moved upwardly into engagement with the lower ring 20 which will prevent ejection of' the drill stem from the casing.

When it is desired to remove the blow out preventer, the dog actuating device 24 (Fig. 4) is employed to move the dogs 22 into their inactive positions. The drill stem may then be elevated and the blow out preventer removed therefrom.

The apparatus shown by Figs. 4 and 5 is the same as that shown by Figs. 1, 2 and 3 except that a different blow out preventer is employed to permit closure of the valve while the drill stem is in the casing. This preventer is indicated at 28. It is frusto-conical in form and includes a pair of sections 29 and 30 hinged at 31; latched at 32; and having dogs 33 urged into their active positions by springs 34 and movable into their inactive positions by device 24 rotatable in openings 35. Fitting in grooves in its periphery are packing rings 36 to sealingly engage seat 13. It also has in its upper portion an. axial recess 37 for the reception of the coupling 25 of the drill stem. The packing ring 38 is employed to seal the drill stem coupling 25 to the blow out preventer.

If, during drilling operations, a blow out is threatened, the blow out preventer 28 may be clamped about the drill stem 5 and dropped through the opening 11 upon the seat 13. The drill stem may then be lowered until the coupling 25 enters the recess 37 and rests upon the packing ring 38. That portion of the drill stem above coupling 25 may then be disconnected therefrom, and the gate valve 6 may be moved across the fluid passageway in the valve body upon the valve seat 8 to completely shut off the flow of fluid.

The valve is adapted for use not only with drilling equipment as herein described; but also with production equipment, which latter use is disclosed in a companion application for Letters Patent.

When oil or any other fluid for which the well is drilled is encountered, it is sometimes desirable to leave the drill stem in the casing rather than to remove it from the casing and insert in its place a tubing. This may readily be done with the apparatus as shown by Fig. 4, because the guide 26 may be removed and a suitable coupling (T1013 shown) put in its place to convey fluid to the conventional flow lines.

The invention is not limited to the preferred embodiments shown. Various changes will occur to those skilled in the art and may be made within the scope of the following claims.

I claim:

1. The combination with a casing, a drill stem, and a blow out preventer, of a casing head valve comprising a body mounted on said casing and having a longitudinal fluid passageway communicating with the interior of said casing, the upper portion of said passageway being larger than the lower portion of said passageway to form a seat for said blow out preventer; said blow out preventer being movable on said drill stem through the upper portionv of said passageway into locking engagement with said seat; and a gate movable between said seat and the upper portion of said passageway to close said passageway.

2. The combination with a casing, a drill stem, and a blow out preventer, of a casing head valve comprising a body mounted on said casing, said body having a main fluid passageway extending therethrough and communicating with the interior of said casing, the upper portion of said passageway being larger than the lower portion of said passageway to form a seat for said blow out preventer, and a branch fluid passageway communicating with the lower portion of said main fluid passageway; said blow out preventer being movable on said drill stem through the upper portion of said passageway into locking engagement with said seat; and a gate movable between said seat and the upper portion of said main passageway to close said main passage way.

3. The combination with a casing, a drill stem, and a blow out preventer on said stem, of a casing head valve mounted on said casing and having an axial fluid passageway extending therethrough and communicating with the interior of said casing; the upper portion of said passageway being larger than the lower portion of said passageway to form a blow out preventer seat; said stem being insertable in said passageway and casing to move said blow out preventer through the upper portion of said passageway into locking engagement with said seat.

4. The combination with a casing, a drill stem, and a blow out preventer on said stem, of a casing head valve mounted on said casing and having a main axial fluid passageway extending therethrough and communicating with the interior of said casing; the upper portion of said passageway being larger than the lower portion of said passageway to form a blow out preventer seat; and a branch passageway communicating with said main passageway below said seat; said stem being insertable in said main passageway and casing to move said blow out preventer through the upper portion of said main passageway into locking engagement with said seat.

5. The combination of a casing; a drill stem; a blow out preventer on said stem; and a casing head valve comprising a body mounted on said casing and having an axial fluid passageway extending therethrough and communicating with the interior of said casing; the upper portion of said passageway being larger than the lower portion of said passageway to form a blow out preventer seat; said stem being insertable in said passageway and casing to move said blow out preventer through the upper portion of said passageway into locking engagement with said seat; said stem comprising sections separable adjacent said blow out preventer; said valve having a gate movable between the upper portion of said passageway and said seat to close said passage way after separation of said sections and withdrawal from said passageway of the upper of said sections.

6. The combination with a casing; a drill stem; a blow out preventer on said stem; and a casing head valve comprising a body mounted on said casing and having a main axial fluid passage way extending thcrethrough and communicating with the interior of said casing; the upper portion of said passageway being larger than the lower portion of said passageway to form a blow out preventer seat; and a branch fluid passageway communicating with said main passageway below said seat; said stem being insertable in said main passageway and casing to move said blow out preventer through the upper portion of said main passageway into locking engagement with said seat; said 'stem comprising sections 

